Pipe hanger

ABSTRACT

A hanger for suspending a pipe string within a well comprising: a tubular body member and a support ring mounted around the body member for axial movement thereon. The body member may be adapted for connection at its upper end to a handling string and at its lower end to the pipe string to be suspended. The body member may be provided with a reduced outside diameter mid-portion and a larger diameter backup portion with stop shoulders at the upper end of the back-up portion and upper end of the mid-portion. The support ring may be axially split along one side so as to be contractable from its unrestrained position and self-expandable from the contracted position to its unrestrained position. The hanger is provided with a release arrangement for holding the ring around the body member mid-portion but being disengageable to allow the ring to move upwardly relative to the body member and around the back-up portion thereof in its unrestrained position until it contacts the stop shoulder at the upper end of the back-up portion. In this position the backup portion locks the ring in its unrestrained position and prevents downward movement of the body member relative to the support ring. In one embodiment the release arrangement is disengageable on contraction of the ring. In another embodiment the release arrangement initially holds the ring around the mid-portion in a collapsed condition. On disengagement the release allows the ring to expand to its unrestrained position for movement to the locked position around the back-up portion.

United States Patent 8119] Herd et al.

[ PIPE HANGER 75 Inventors: David P. Herd; John w. McCaskill; James V. Bonds, all of Houston, Tex.

[73] Assignee: Rockwell Manufacturing Company,

' Houston, Tex.

[22] Filed: Nov. 11, 1971 [21] Appl. No.: 198,000

Related U.S. Application Data [63] Continuation of Ser. No. 862,887, 0a. 1, 1969,

' 285/308,3l7,314, 321, 18,3,4, 24, 27,010. Y 1 21;287/D1G. 7

[56] References Cited UNlTED STATES PATENTS 3,405,763 10/1968 Pitts et al 285/141 x 3,424,477 1/1969 Putch et al.. 285/142 X Crain et al.. 285/18 X Maeshiba 285/317 X Primary Examinerf-Dave W. Arola Attorney-Murray Robinson et al.

57 I ABSTRACT A. hanger for suspending a pipe string within a well June 26, 1973 comprising: a tubular body member and a support ring mounted around the body member for axial movement thereon. The body member may be adapted for connection at its upper end to a handling string and at its lower end to the pipe string to be suspended. The body member may be provided with a reduced outside diameter mid-portion and a larger diameter backup portion with stop shoulders at the upper end of the back-up portion and upper end of the mid-portion. The support ring may be axially split alongone side so as to be contractable from its unrestrained position and selfexpandable from the contracted position to its unrestrained position. The hanger is provided with a release arrangement for holding the ring around the body member mid-portionbut being disengageable to allow the ring to move upwardly relative to the body member and around the back-up portion thereof in its unrestrained position until it contacts the stop shoulder at the upper end of the back-up portion. In this position the backup portion locks the ring in its unrestrained position and prevents downward movement of the body member relative to the support ring. In one embodiment the release arrangement is disengageable on contraction of the ring. In another embodiment the release arrangement initially holds the ring around the midportion in a collapsed condition. On disengagement the release allows the ring to expand to its unrestrained position for movement to the locked position around the backup portion.

22 Claims, 13 Drawing Figures Unified States Patent 1 [111 3,741,589

Herd et al. v June 26, 1973 i iii L PIPE HANGER This is a continuation of 1 application Ser. No. 862,887, filed Oct. 1, 1969, and now abandoned.

BACKGROUND OF THE. INVENTION 1. Field of the Invention This invention pertains to oil and gas well apparatus. More specifically, it concerns apparatus used to hang casing or tubing within a well. 2. Description of the Prior Art Normally, casing and tubing strings are supported in ers comprised a solid mandrel with a support ring or shoulder which rested on an upwardly facing shoulder in the'wellhead. However, in recently used methods, particularly offshore methods, this design is not suitable. For example, in extended casing methods, which are becoming more and, more popular, the wellhead may be located at the mudline with risers connected thereabove for extension to the surface. Normally the risers are the same size as their respective down-thehole casing strings. With the old standard solid mandrel hanger, drilling tools and other down-the-hole equipment are limited in size by the wellhead support shoulder rather than the casing diameter. To eliminate this problem, hangers with various retractable type hanging mechanisms have been developed. The most common type used has been one which comprises aplurality of spring-loaded latch segments. The bottom edge of the segments are tapered so that they will cam in upon entry into the bit guide and riser through which the hanger must pass before reaching the wellhead or hanger-head, as they are sometimes called. The lead-in taper also prevents hang-up in blowa wellhead by a hanging device. In the past, most hangout prevention equipment. Hangers of this design are clearly shownin U.S. Pat. No. 3,421 ,580 issued on Janeter portion which then drops behind the spring ring locking the ring against inward movement and the hanger against downward movement.

One embodiment shown has a lip type arrangement to hold the spring in a non-engaging position until the hanger enters the riser. It is then released, but cammed inwardly by the riser until it reaches the support recesses. Another embodiment utilizes a unique latch release mechanism which holds the ring in its collapsed position until it reaches the level of the support recesses where it is released. Other features of the invention pointed out in the claims can best be set forth in the description which follows.

BRIEF DESCRIPTION OF THE DRAWINGS For a detailed description of preferred embodiments of the invention, reference will be made to the accom- I panying drawings, but these are only exemplary of the invention which can be varied by one skilled in the art.- In the drawings:

FIG. 1 is a vertical quarter section showing one embodiment, of the invention;

FIG. 2 is a horizontal section of the embodiment of FIG. 1 taken along line 22 thereof;

FIG. 3 is another horizontal section of the embodiment of FIG. 1 taken along line 3-3 thereof;

FIGS. 4, 5 and 6 are partial vertical quarter section views of the embodiment of FIG. 1 showing the hanger in various stages as it is lowered into a wellhead,

FIG. 7 is an elevation view in section of another embodiment of the invention showing the hanger in its initial position of engagement in a hanger head;

FIG. 8 is an elevation view partially in section, rotated ninety degrees from the view of FIG. 7;

FIG. 9 is an elevation view in section of the embodiment of FIGS. 7 and 8 showing the hanger in its final support position within a hanger-head;

uary 14,1969. This patent also gives a good description of an extende'd'casing drilling method. However, these spring loaded latch type hangers do have some defi- ,cienciesli Full engagement of the latches into their hanger' recesses is solely dependent on spring loading to overcome anyforeign matter which may be present in the recesses. To sus'pe'nd maximum casing weight, these latches must be fully engaged. Furthermore,it is necessary to provide a rather complex mounting arrangementfor the latches to prevent their coming off of the hanger body when it is out of the hole. Many of them also have no means of lockingthe latches in place to prevent accidental disengagement. Other. designs have eliminated the plurality of spring loaded latches. For example, US. Pat. No. 3,420,308 issued on Jan. 7, I969 disclosed a single spring ring latch. However, these designs also present problems in the manner of energizing and locking the latches in place.

SUMMARY OF THE INVENTION When the hanger reaches the recesses the ring is allowed to expand to its unrestrained position engaging the recesses. The hanger body has another larger diamrecesses for selectively supporting two hangers similar to the one shown in FIGS. 7 through 10;

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring first to FIGS. 1 through 6, one embodiment of the invention will be described. The hanger of this embodiment comprises a tubular body portion 10 and a support ring portion 30. Body 10 may be provided with upper and lower connection means such as threads I1, 12 respectively for connection to a casing 2, to be supported thereby and a handling joint or riser Body 10 has a reduced diameter mid-portion 13, a slightly larger diameter back-up or locking portion 14, upper stop shoulder 15 and lower stop shoulder 16. Lower stop shoulder I6 is provided with upwardly projecting circumferentialrim 17 with a lip 18 projecting inwardly from rim l7. Mid-portion 13 is connected to back-up portion 14 by downwardly facing intermediate stop shoulder 20 and frustoconical surface 21. Back-up portion 14, upper stop shoulder and lower stop shoulder 16 may be fluted as at 22 to provide a passageway for fluid returns for cementing and the like.

Support ring 30 is axially split along one side by the removal of a section so that the opposed ends of the ring 32 and 34 in the unrestrained position shown in FIGS. 1 through 3 are separated by some distance. This allows the ring to be collapsed or contracted. The ring 30, could be solid throughout. However, for flexibility and flow passage purposes it may be segmented as shown. It may comprise a lower continuous body ring 36, guide segments 37 and support segments 38. Near the junction of guide segments 37 and support segment 38, holes 40 may be formed in communication with the interior and exterior of the support ring to cooperate with the hanger body flutes 22 to provide fluid passage. The lower edge of ring 36 is provided with an outwardly projecting lip 42 which cooperates with rim lip 18 to initially hold ring 30 in the position shown in FIG. 1. This prevents ring 30 from prematurely sliding upwardly around back-up portion 14.

Referring now to FIG. 4, as the hanger is lowered into a surrounding casing or riser 50, the lower camming surface 52 of guide segments 37 causes support ring 30 to be contracted to a point where cooperating lip 18 and 42 are disengaged. This allows support ring 30 to move upwardly relative to and around body midportion 13, as the hanger moves downwardly in riser 50, until the upper surface of support segments 38 contact the downwardly facing intermediate stop shoulder as in FIG. Thus, lips 18 and 42 are completely out of axial alignment and will not affect expansion of ring 30.

As the hanger approaches its final support position, as shown in FIG. 6, guide segments 37 and support segments 38 encounter cooperativecorrelative recesses 54 in wellhead 58 and spring outwardly to engage them so that support ring 30 is in its fully expanded or unrestrained position. This allows hanger body 10 and backup portion 14 to move downwardly relative to ring 30 until upper stop shoulder 15 comes to rest against the upper surface of support segments 38. If ring 30 does not expand completely due to foreign material which may be in recesses 54, the frusto-conical surface 21 will force it to do so. In this position ring 30 is locked against further downward movement assuring positive support of its attached casing string. Cementing may be performed by returning fluids upwardly through annular space 56, the hanger body fluted areas 22, the spaces between guide segments 37, and fluid passages 40. If for some reason it is desired to remove the hanger and its supported casing before cementing, it is a simple matter. An upward force will cause the hanger body 10 to move upwardly until ring 30 is free of backup portion 14. The upper tapered surfaces of support segments 38 and guide segments 37 cooperate with corresponding tapers in recesses 54 to contract ring 30 around mid-portion 13. Ring 30 then moves downwardly relative to body 10 until lip 42 contacts lower stop shoulder 16. If the hanger is completely removed from the surrounding pipe or riser the ring 30 will again expand with-lips 42 and 18 re-engaging as in the initial position shown in FIG. 1.

Referring now to FIGS. 7 through 10, another embodiment of the invention will be described. This embodiment is similar to the one previously described.

The hanger, supporting a casing string 102 and run on a riser 101, comprises a tubular body portion and a spring ring portion which is also axially split along one side providing spaced apart opposing end surfaces 132 and 134. For purposes of illustration, ring 130 is shown as being solid. It could be divided into segments as the ring of the previously described embodiment.

Body 110 has a reduced external diameter midportion 113, a larger diameter back-up portion 114, upper stop shoulder 115 and lower stop shoulder 116. The body may be fluted as at 122 to provide for flow returns as previously discussed with reference to the prior embodiment.

One major difference in this embodiment is in its method of releasing the ring for engagement with a wellhead recess 154. Instead of using the cooperative lip arrangement of the prior embodiment, a latch release assembly is provided. The latch release assembly 160 comprises a carrier 162 and an elongate releasing latch 164. Carrier 162 rides in a slot 123 of hanger body 110 and is initially held at the lower position shown in FIGS. 7 and 8 by shear pin 166 which passes through housing 162 and into holes in hanger body 110. Suspension ring 130 is contracted or collapsed about mid-portion 113 and held in this position by restraining pins which project out of carrier 162 into vertical holes drilled in the upper surface of ring 130. The lower edge of ring 130 is also constrained by a circumferential lip 163 in engagement with circumferential groove 142 around body 110.

Releasing latch 164 rides in a slot 168 in carrier 162 and is free to pivot about pin 169. A leaf spring 170 is attached to latch 164 by screw 17] and biases the latch outwardly. As the hanger assembly is lowered through blowout preventers and surface equipment the rounded leading edge 172 of latch 164 cams the latch in. With some sizes another guide leaf spring 175 and pin 176 may be required to prevent hang-up in the blowout preventers. The tapered leading edge angle is such that the horizontal force component is sufficient to overcome the preload of leaf spring 170 while the vertical force component is insufflcient to shear pin 166. The releasing latch 164, therefore, collapses and the hanger enters the casing riser 150. One distinct advantage of this embodiment is that ring 130 does not drag on the wall of riser 150. Only latch 164 does so resulting in very little wear on riser 150.

The profile of latch 164 is such that it will not engage a coupling gap but will engage recesses 154 in wellhead or hanger-head 158. As casing weight is set down on the releasing latch 164, pin 166 shears. Carrier 162 is held stationary'by latch 164 and hanger body 110 continues to move downwardly. Guide slots 180 in carrier 162 and guide pin 18] afflxed to hanger body 110 allows relative movement of carrier 162 within hanger body slot 123. Suspension ring 130 is in contact with shoulder 144 and moves down with hanger body 110. In a short distance of relative travel, e.g., less than an inch, ring 130 disengages restraining pins 165. Ring 130 is then free to expand into contact with the bore of hanger-head 158.

Continued downward travel pushes ring 130 into recesses 154 as better shown in FIGS. 9 and 10. Should ring 130 be unable to completely expand into recesses 154 the taper or frusto-conical surface 146 on hanger body 110 contacts the inside diameter of ring 130 and wedges the ring into full engagement with the recesses 154. The upper stop shoulder 115 then engages the upper edge of ring 130 preventing further downward travel of hanger body 110 and fully supporting casing 102 in hanger-head 158. The back-up portion 114 positively locks ring 130 in its fully engaged position. During cementing of the suspended casing string 102, cement returns pass behind support ring 130 and through one or more flutes 122 in hanger body 110.

The hanger can be retrieved simply by pulling upwardly thereon. Since small shear pin 166 has been sheared, carrier 162 will be retained by guide pins 181 which ride in guide slots 180.

Minor changes in configuration would increase the versatility of this hanger design. Modification to releasing latch 164 and a different set of hanger recesses would permit selective release of hanger support ring 130. For example, with reference to FIG. 11, another hanger-head 198 with another set of recesses 194 could be installed at some point below hanger-head 158. A casing string (not shown) could then be suspended in hangerhead 194 using a hanger identical to the one just described except for modification of the latch 164. Then a tubing string (not shown) could be suspended in hanger-head 154 by a hanger similar to the one just described, modified to receive a tubing string rather would be increased from L, as in recesses 154 to L as indicated by the dotted lines. 'Thus, as the casing hanger to be suspended in hanger-head 198 passed through hanger-head 158 the increased length X of land 191 being greater than upper groove length L of recesses 154 would prevent engagement. However, when the hanger reached hanger-head 198 with its increased upper recess groove length L the modified latch would engage and the hanger would function as previously described. Then the tubing hanger could be run and suspended in hanger-head 158 with an unmodified latch 164.

- Another application of selective releasing is in the use of tension type hangers where it is required that tension beapplied to a tubing string afterthe packer is set. To set tension, the tubing hanger must be-below the desired setting point when thepackeris set. Therefore, thehanger mechanism cannot set the'first time it passes through the recesses of its final support position but must engage the recesses when pulled back up. To accomplish this the tu bing hanger would be'provided with a modified latch as 'shownby the dotted lines in FIG.

. 12. Two sets ofrecesses similar to 154 and 194 in FIG.

ment would apply tension to the tubing. Since the hanger mechanism has been released, it would engage recesses 154 when the tubing hanger is pulledupwardly to that level. The hanger would then be set as previously described maintaining tension in the tubing string.

Two preferred embodiments and several modifications of spring ring type hangers have been described herein. These hangers permit the lowering of drills and other down-the-hole well equipment having diameters only slightly less than the full bore diameter of casing through which it passes. Unique release mechanisms for setting the hangers have been shown along with several applications thereof. Although these hangers incorporate novel concepts they are economically constructed and simple to operate.

We claim:

1. A hanger for suspending a pipe string within a well, comprising: a tubular body member and a support ring mounted around said body member for axial movement thereon, said body member being adapted for connection at its upper end to a handling string and at its lower end to a pipe string, said body member having a reduced outside diameter mid-portion, a larger diameter back-up portion above said mid-portion, a downwardly facing upper stop shoulder at the upper end of said back-up portion and a downwardly facing intermediate stop shoulder at the upper end of said mid-portion, said support ring being axially split along one side thereof, said ring being contractable from an unrestrained posi tion to a collapsed position and self-expandable from said collapsed position to said unrestrained position; release means on said ring and'said body member holding said ring around said mid-portion and preventing axial movement of said ring from 'said mid-portion to said back-up portion, and abutment means including a downwardly directed surface to effect disengagement of said release means upon said abutment means encountering an abutment resisting further downward movement of said abutment means when said pipe string is lowered into the well, said release means being disengageable to allow said ring to move upwardly relative to said body member and around said back-up portion in its unrestrained position until said ring contacts said upper stop shoulder, said back-up portion locking said ring in said unrestrained position and preventing downward movement of said body member relative to said support ring. i

'2. A pipe hanger as set forth in claim 1 characterized in that said intermediate stop shoulder is connected to said back-up portion by a downwardly facing frustoconical surface, the upper endof said ring having an upwardly facing frustoconical surface at its inner periphery.

3. A hanger for suspending a pipe string within a well, I

comprising: a tubular body member and a support ring mounted around said body member for axial movement thereon, said body member being adapted for connection at its upper end to a handling string and at its lower end to a pipe string, said body member having a reduced outside diameter mid-portion, a larger diameter back-up portion above said mid-portion, a downardly facing upper stop shoulder at the upper end of said back-up portion and a downwardly facing intermediate stop shoulder at the upper end of said mid-portion said support ring being axially split along one side thereof, said ring being contractable from an unrestrained position to a collapsed position and self-expandable from said collapsed position to said unrestrained position; release means on said ring and said body member holding said ring around said mid-portion and preventing axial movement of said ring from said mid-portion to said back-up portion, said release means being disengageable to allow said ring to move upwardly relative to said body member and around said back-up portion in its unrestrained position until said ring contacts said upper stop shoulder, said back-up portion locking said ring in said unrestrained position and preventing downward movement-of said body member relative to said support ring, characterized in that said release means comprises an inwardly projecting lip on the exterior of said body member in engagement with an outwardly projecting lip on said ring, said lips being disengageable on contraction of said ring to permit movement of said ring to said locked position around said back-up portion.

4. A hanger for suspending a pipe string within a well, comprising: a tubular body member and a support ring mounted around said body member for axial movement thereon, said body member being adapted for connection at its upper end to a handling string and at its lower end to a pipe string, said body member having a reduced outside diameter mid-portion, a larger diameter back-up portion above said mid-portion, a downwardly facing upper stop shoulder at the upper end of said back-up portion and a downwardly facing intermediate stop shoulder at the upper end of said mid-portion, said support ring being axially split along one side thereof, said ring being contractable from an unrestrained position to a collapsed position and self-expandable from said collapsed position to said unrestrained position; release means on said ring and said body member holding said ring around said mid-portion and preventing axial movement of said ring from said mid-portion to said back-up portion, said release means being disengageable to allow said ring to move upwardly relative to said body member and around said back-up portion in its unrestrained position until said ring contacts said upper stop shoulder, said back-up portion locking said ring in said unrestrained position and preventing downward movement of said body member relative to said support ring, characterized in that the length of said mid-portion of said body member is substantially greater than the axial length of said ring permitting, when said release means is disengaged, limited axial movement of said ring on said mid-portion to a point where said release means is non-engageable.

5. A pipe hanger as set forth in claim 1, characterized in that said release means comprises restraining means engaging said ring and holding said ring in a collapsed position around said mid-portion, said restraining means being disengageable from said ring to permit expansion and movement of said ring to said unrestrained and locked position around said back-up portion, said restraining means comprising elements engageable with said ring by downward movement of said restraining means relative to said ring and disengageable from said ring by upward movement of said restraining means relative to said ring.

6. A pipe hanger as set forth in claim 5, characterized in that said restraining means comprises pins mounted in a housing member, said pins engaging holes in one edge of said support ring, said housing member being mounted on said body member and attached thereto by shear means, said housing member and said pins being moveable on said body member on shearing of shear means for said disengagement from said ring to permit said expansion and movement of said ring to said unrestrained and locked position.

7. A hanger for suspending a pipe string within a well, comprising: a tubular body member and a support ring mounted around said body member for axial movement thereon, said body member being adapted for connection to a handling string at its upper-end and a pipe string at its lower end, said body member having a reduced outside diameter portion, a larger diameter back-up portion above said reduced portion, a downwardly facing upper stop shoulder at the upper end of said back-up portion and a downwardly facing intermediate stop shoulder at the upper end of said reduced diameter portion and an upwardly facing stop shoulder at the lower end of said reduced diameter portion, said support ring being axially split along one side thereof to permit contraction of said ring from an unrestrained position to a collapsed position and self-expansion from said collapsed position to said unrestrained position, release means on said ring and said body member holding said ring in a position wherein it is disposed around said reduced diameter portion and preventing axial movement thereon, said release means comprising elements on said ring and body engageable upon expansion of said ring from said collapsed position and disengageable upon contraction of said ring from the position achieved by said expansion, and cam means connected to said ring to effect said contraction of said ring and disengagement of said release means upon said cam means encountering an abutment preventing further downward movement of said cam means when said pipe string is lowered into the well, said ring upon disengagement of said release means being free for limited axial movement of said ring from said lower stop shoulder to contact with said intermediate stop shoulder and, on self-expansion of said ring, from said intermediate stop shoulder to contact with said upper stop shoulder and around said back-up portion, said upper stop shoulder and said back-up portion locking said ring in said unrestrained position and preventing downward movement of said body member relative to said support ring.

8. A pipe hanger as set forth in claim 7, characterized in that passage means are formed in said support ring in communication with the interior and exterior thereof.

9. A pipe hanger as set forth in claim 7, characterized in that said release means comprises a lip around the lower edge of said support ring in engagement with a lip around said body member near the lower end of said mid-portion, said lips preventing axial movement of said ring on said body member but being disengageable on said contraction to permit said limited axial movement thereof.

10. A pipe hanger as set forth in claim 9, characterized in that the length of said mid-portion is greater than the axial length of said support ring so that said lips are non-engageable when said support ring is in contact with said intermediate stop shoulder.

11. A pipe hanger as set forth in claim 7 and a surrounding tubular member for supporting said pipe hanger therein, said supporting member having annular recesses on the interior thereof corresponding with the exterior of said support ring in the unrestrained position, said back-up portion being adapted to lock said ring in said recesses to prevent downward movement of ring mounted around said body member for axial movement thereon, said body member. being adapted for connection at its upper end to a-handling string and at its lower end to a pipe string, said body member having a reduced outside diameter mid-portion and a downwardly facing upper stop shoulder at the upper end of said back-up portion, said support ring being axially split along one side thereof providing spaced apartopposing end surfaces to permit contraction of said ring from an unrestrained position to a collapsed position and self expansion from said collapsed position to said unrestrained position, release means on said ring and said body holding said ring around said midportion in a collapsed position, said release means being disengageable to allow expansion of said ring to said unrestrained position and to allow upward movement of said ring around said back-up portion until said ring contacts said upper stop shoulder so that said back-up portion locks said ring in said unrestrained position and prevents downward movement of said body member relative to said support ring, and abutment means including a downwardly directed surface to effect disengagement of said release means upon said abutment means encountering an abutment preventing further downward movement of said abutment means when said pipe string is lowered into the well.

13. A pipe hanger as set forth in claim 12, characterized in that said release means comprises restraining means engaging said ring at the upper edge thereof near said opposing end surfaces and holding said ring in said collapsed position around said mid-portion.

14. A pipe hanger as set forth in claim 13, characterized in that said restraining means comprises pins engaging holes in said upper edge of said support ring, saidpins being mounted on carrier means disposed above said ring for longitudinal upward movement relative to said ring to release said ring for said expansion to said unrestrained position.

15. A pipe hanger as set-forth in claim 14, characterized in that saidabutment means comprises a latch member attached to said carrier means and extending below said carrier means between said end surfaces of said ring, said downwardly directed surface of said abutment means being disposed on said latch member below said carrier means and being adapted for engage ment with an abutment provided by annular recess means in asurrounding tubular member to release said carrier means forsaid longitudinal movement. I

16. A pipe hanger as set forth in claim 15, characterized in that said latch is an elongate member pivotally attached at its upper end to said carrier means, the lower end being biased outwardly from said body member by spring means.

I 17. Apparatus for suspending a pipe string within a well comprising: a pipe hanger'a'nd a surrounding tubular support member having a pair of annular recess means therein defining therebetween inwardly directed radial flange means, said pipe hanger comprising a tubular body member and a support ring mounted around said body member for axial movement thereon, said up portion adjacent said mid-portion and a horizontal annular stop shoulder at one end of said back-up portion, said support ring being axially split along one side thereof providing spaced apart opposing end surfaces to permit contraction of said ring from an unrestrained position to a collapsed position and self-expansion from said collapsed position to said unrestrained position, the outer surface of said ring in said unrestrained position corresponding to the shape of said annular recess means and including annular groove means to receive said radial flange means, release means on said ring and said body holding said ring around said mid-portion in a collapsed position, said release means being disengageable to allow expansion of said ring to said unrestrained position and to allow axial movement of said ring around said back-up portion until said ring contacts said stop shoulder so that said back-up portion locks said ring in said unrestrained position in full engagement with said recess means and radial flange means, preventing downward movement of said pipe hanger and its supported pipe string relative to said tubular support member, and abutment means including a downwardly directed surface to effect disengagement of said release means upon said abutment means encountering said radial flange means preventing further downward movement of said abutment means when said pipe string is lowered into the well, said abutment means corresponding to the shape of said annular recess means and including groove means to receive said radial flange means.

18. Suspension apparatus as set forth in claim 17, characterized in that said release means comprises restraining means engaging said ring at the upper end thereof near said opposing end surfaces and holding said ring in said collapsed position around said midportion.

19. Suspension apparatus as set forth in claim 18, characterized in that said abutment means comprises carrier means disposed above said ring and a latch member mounted on said carrier means and extending below said carrier means between said end surfaces of said ring, said downwardly-directed surface of said abutment means being disposed on said latch member below said carrier means, said' latch member being biased outwardly from said body member for engagement with said annular recess means and said radial flange to release said restraining means on axial movement of said body member relative to said tubular support member to release said ring for said expansion to said unrestrained position.

20. Suspension apparatus as set forth in claim 19, characterized in that said annular recess means comprises at least two pairs of annular recesses each with annular radial flange means therebetween, said pairs .being axially displaced from one another, said latch member being adapted for engagement with one pair but non-engageable with the other pair.

21. Suspension apparatus as set forth in claim 19 characterized in that said restraining means comprises pins attached to and extending downwardly from said carrier engaging holes in said upper edge of said support ring, said carrier holding said pinsin said engagement with said holes, said carrier means being attached to said body member by shear means shearable on said engagement of said latch member and-downward axial movement of said body member to allow upward axial characterized in that said latch member is pivotally attached at its upper end to said carrier, the lower end being provided with a tapered leading edge to prevent premature engagement of said latch member prior to engagement with said recess means. 

1. A hanger for Suspending a pipe string within a well, comprising: a tubular body member and a support ring mounted around said body member for axial movement thereon, said body member being adapted for connection at its upper end to a handling string and at its lower end to a pipe string, said body member having a reduced outside diameter mid-portion, a larger diameter back-up portion above said mid-portion, a downwardly facing upper stop shoulder at the upper end of said back-up portion and a downwardly facing intermediate stop shoulder at the upper end of said mid-portion, said support ring being axially split along one side thereof, said ring being contractable from an unrestrained position to a collapsed position and selfexpandable from said collapsed position to said unrestrained position; release means on said ring and said body member holding said ring around said mid-portion and preventing axial movement of said ring from said mid-portion to said back-up portion, and abutment means including a downwardly directed surface to effect disengagement of said release means upon said abutment means encountering an abutment resisting further downward movement of said abutment means when said pipe string is lowered into the well, said release means being disengageable to allow said ring to move upwardly relative to said body member and around said back-up portion in its unrestrained position until said ring contacts said upper stop shoulder, said back-up portion locking said ring in said unrestrained position and preventing downward movement of said body member relative to said support ring.
 2. A pipe hanger as set forth in claim 1 characterized in that said intermediate stop shoulder is connected to said back-up portion by a downwardly facing frusto-conical surface, the upper end of said ring having an upwardly facing frustoconical surface at its inner periphery.
 3. A hanger for suspending a pipe string within a well, comprising: a tubular body member and a support ring mounted around said body member for axial movement thereon, said body member being adapted for connection at its upper end to a handling string and at its lower end to a pipe string, said body member having a reduced outside diameter mid-portion, a larger diameter back-up portion above said mid-portion, a downardly facing upper stop shoulder at the upper end of said back-up portion and a downwardly facing intermediate stop shoulder at the upper end of said mid-portion said support ring being axially split along one side thereof, said ring being contractable from an unrestrained position to a collapsed position and self-expandable from said collapsed position to said unrestrained position; release means on said ring and said body member holding said ring around said mid-portion and preventing axial movement of said ring from said mid-portion to said back-up portion, said release means being disengageable to allow said ring to move upwardly relative to said body member and around said back-up portion in its unrestrained position until said ring contacts said upper stop shoulder, said back-up portion locking said ring in said unrestrained position and preventing downward movement of said body member relative to said support ring, characterized in that said release means comprises an inwardly projecting lip on the exterior of said body member in engagement with an outwardly projecting lip on said ring, said lips being disengageable on contraction of said ring to permit movement of said ring to said locked position around said back-up portion.
 4. A hanger for suspending a pipe string within a well, comprising: a tubular body member and a support ring mounted around said body member for axial movement thereon, said body member being adapted for connection at its upper end to a handling string and at its lower end to a pipe string, said body member having a reduced outside diameter mid-portion, a larger diameter back-up portion above said mid-portion, a downwardly facing upper stop shoulder at the upper end of said back-up portion and a downwardly facing intermediate stop shoulder at the upper end of said mid-portion, said support ring being axially split along one side thereof, said ring being contractable from an unrestrained position to a collapsed position and self-expandable from said collapsed position to said unrestrained position; release means on said ring and said body member holding said ring around said mid-portion and preventing axial movement of said ring from said mid-portion to said back-up portion, said release means being disengageable to allow said ring to move upwardly relative to said body member and around said back-up portion in its unrestrained position until said ring contacts said upper stop shoulder, said back-up portion locking said ring in said unrestrained position and preventing downward movement of said body member relative to said support ring, characterized in that the length of said mid-portion of said body member is substantially greater than the axial length of said ring permitting, when said release means is disengaged, limited axial movement of said ring on said mid-portion to a point where said release means is non-engageable.
 5. A pipe hanger as set forth in claim 1, characterized in that said release means comprises restraining means engaging said ring and holding said ring in a collapsed position around said mid-portion, said restraining means being disengageable from said ring to permit expansion and movement of said ring to said unrestrained and locked position around said back-up portion, said restraining means comprising elements engageable with said ring by downward movement of said restraining means relative to said ring and disengageable from said ring by upward movement of said restraining means relative to said ring.
 6. A pipe hanger as set forth in claim 5, characterized in that said restraining means comprises pins mounted in a housing member, said pins engaging holes in one edge of said support ring, said housing member being mounted on said body member and attached thereto by shear means, said housing member and said pins being moveable on said body member on shearing of shear means for said disengagement from said ring to permit said expansion and movement of said ring to said unrestrained and locked position.
 7. A hanger for suspending a pipe string within a well, comprising: a tubular body member and a support ring mounted around said body member for axial movement thereon, said body member being adapted for connection to a handling string at its upper-end and a pipe string at its lower end, said body member having a reduced outside diameter portion, a larger diameter back-up portion above said reduced portion, a downwardly facing upper stop shoulder at the upper end of said back-up portion and a downwardly facing intermediate stop shoulder at the upper end of said reduced diameter portion and an upwardly facing stop shoulder at the lower end of said reduced diameter portion, said support ring being axially split along one side thereof to permit contraction of said ring from an unrestrained position to a collapsed position and self-expansion from said collapsed position to said unrestrained position, release means on said ring and said body member holding said ring in a position wherein it is disposed around said reduced diameter portion and preventing axial movement thereon, said release means comprising elements on said ring and body engageable upon expansion of said ring from said collapsed position and disengageable upon contraction of said ring from the position achieved by said expansion, and cam means connected to said ring to effect said contraction of said ring and disengagement of said release means upon said cam means encountering an abutment preventing further downward movement of said cam means when said pipe string is lowered into the well, said ring upon disengagement of said release means being free for limited axial movement of said ring from said lower stop shoulder to contact with saiD intermediate stop shoulder and, on self-expansion of said ring, from said intermediate stop shoulder to contact with said upper stop shoulder and around said back-up portion, said upper stop shoulder and said back-up portion locking said ring in said unrestrained position and preventing downward movement of said body member relative to said support ring.
 8. A pipe hanger as set forth in claim 7, characterized in that passage means are formed in said support ring in communication with the interior and exterior thereof.
 9. A pipe hanger as set forth in claim 7, characterized in that said release means comprises a lip around the lower edge of said support ring in engagement with a lip around said body member near the lower end of said mid-portion, said lips preventing axial movement of said ring on said body member but being disengageable on said contraction to permit said limited axial movement thereof.
 10. A pipe hanger as set forth in claim 9, characterized in that the length of said mid-portion is greater than the axial length of said support ring so that said lips are non-engageable when said support ring is in contact with said intermediate stop shoulder.
 11. A pipe hanger as set forth in claim 7 and a surrounding tubular member for supporting said pipe hanger therein, said supporting member having annular recesses on the interior thereof corresponding with the exterior of said support ring in the unrestrained position, said back-up portion being adapted to lock said ring in said recesses to prevent downward movement of said hanger therein but allowing upward movement of said hanger.
 12. A hanger for suspending a pipe string within a well, comprising: a tubular body member and a support ring mounted around said body member for axial movement thereon, said body member being adapted for connection at its upper end to a handling string and at its lower end to a pipe string, said body member having a reduced outside diameter mid-portion and a downwardly facing upper stop shoulder at the upper end of said back-up portion, said support ring being axially split along one side thereof providing spaced apart opposing end surfaces to permit contraction of said ring from an unrestrained position to a collapsed position and self expansion from said collapsed position to said unrestrained position, release means on said ring and said body holding said ring around said mid-portion in a collapsed position, said release means being disengageable to allow expansion of said ring to said unrestrained position and to allow upward movement of said ring around said back-up portion until said ring contacts said upper stop shoulder so that said back-up portion locks said ring in said unrestrained position and prevents downward movement of said body member relative to said support ring, and abutment means including a downwardly directed surface to effect disengagement of said release means upon said abutment means encountering an abutment preventing further downward movement of said abutment means when said pipe string is lowered into the well.
 13. A pipe hanger as set forth in claim 12, characterized in that said release means comprises restraining means engaging said ring at the upper edge thereof near said opposing end surfaces and holding said ring in said collapsed position around said mid-portion.
 14. A pipe hanger as set forth in claim 13, characterized in that said restraining means comprises pins engaging holes in said upper edge of said support ring, said pins being mounted on carrier means disposed above said ring for longitudinal upward movement relative to said ring to release said ring for said expansion to said unrestrained position.
 15. A pipe hanger as set forth in claim 14, characterized in that said abutment means comprises a latch member attached to said carrier means and extending below said carrier means between said end surfaces of said ring, said downwardly directed surface of said abutment means being disposed on said latch member below saId carrier means and being adapted for engagement with an abutment provided by annular recess means in a surrounding tubular member to release said carrier means for said longitudinal movement.
 16. A pipe hanger as set forth in claim 15, characterized in that said latch is an elongate member pivotally attached at its upper end to said carrier means, the lower end being biased outwardly from said body member by spring means.
 17. Apparatus for suspending a pipe string within a well comprising: a pipe hanger and a surrounding tubular support member having a pair of annular recess means therein defining therebetween inwardly directed radial flange means, said pipe hanger comprising a tubular body member and a support ring mounted around said body member for axial movement thereon, said body member being adapted for connection at its upper end to a handling string and at its lower end to said pipe string for suspension in said well and having a reduced outside diameter mid-portion, a larger diameter back-up portion adjacent said mid-portion and a horizontal annular stop shoulder at one end of said back-up portion, said support ring being axially split along one side thereof providing spaced apart opposing end surfaces to permit contraction of said ring from an unrestrained position to a collapsed position and self-expansion from said collapsed position to said unrestrained position, the outer surface of said ring in said unrestrained position corresponding to the shape of said annular recess means and including annular groove means to receive said radial flange means, release means on said ring and said body holding said ring around said mid-portion in a collapsed position, said release means being disengageable to allow expansion of said ring to said unrestrained position and to allow axial movement of said ring around said back-up portion until said ring contacts said stop shoulder so that said back-up portion locks said ring in said unrestrained position in full engagement with said recess means and radial flange means, preventing downward movement of said pipe hanger and its supported pipe string relative to said tubular support member, and abutment means including a downwardly directed surface to effect disengagement of said release means upon said abutment means encountering said radial flange means preventing further downward movement of said abutment means when said pipe string is lowered into the well, said abutment means corresponding to the shape of said annular recess means and including groove means to receive said radial flange means.
 18. Suspension apparatus as set forth in claim 17, characterized in that said release means comprises restraining means engaging said ring at the upper end thereof near said opposing end surfaces and holding said ring in said collapsed position around said mid-portion.
 19. Suspension apparatus as set forth in claim 18, characterized in that said abutment means comprises carrier means disposed above said ring and a latch member mounted on said carrier means and extending below said carrier means between said end surfaces of said ring, said downwardly directed surface of said abutment means being disposed on said latch member below said carrier means, said latch member being biased outwardly from said body member for engagement with said annular recess means and said radial flange to release said restraining means on axial movement of said body member relative to said tubular support member to release said ring for said expansion to said unrestrained position.
 20. Suspension apparatus as set forth in claim 19, characterized in that said annular recess means comprises at least two pairs of annular recesses each with annular radial flange means therebetween, said pairs being axially displaced from one another, said latch member being adapted for engagement with one pair but non-engageable with the other pair.
 21. Suspension apparatus as set forth in claim 19 characterized in that said restraining means comprIses pins attached to and extending downwardly from said carrier engaging holes in said upper edge of said support ring, said carrier holding said pins in said engagement with said holes, said carrier means being attached to said body member by shear means shearable on said engagement of said latch member and downward axial movement of said body member to allow upward axial movement of said carrier and said pins relative to said body member to release said ring for said expansion to said unrestrained position.
 22. Suspension apparatus as set forth in claim 21 characterized in that said latch member is pivotally attached at its upper end to said carrier, the lower end being provided with a tapered leading edge to prevent premature engagement of said latch member prior to engagement with said recess means. 